PURPOSE: To form a deposited metal into the uniform structure free from high- temp. cracking in combining of a hollow steel ingot by an electroslag method by shifting uniformly the dropping position of a consumable electrode near the inside surface of a hollow steel ingot thereby improving deposition and heat radiation and shallowing a molten pool.

CONSTITUTION: An annular electrode or plural small-diameter electrodes are used for a consumable electrode 4 and the molten steel 13 dropping from the tip thereof is deviated near the inside surface of a hollow steel ingot in the production of a composite steel ingot by using the hollow steel ingot 1 as a metallic mold and performing electroslag refining by the same or different electrodes 4. The deposition of the molten steel to the ingot 1 is improved and the heat radiation is improved in this case. Since the central part does not heat up to the max. temp. part, a molten pool 3 is made shallow and the contact angle of the crystal grains having inverse V structure is made small by which the high-temp. cracking is prevented. If the ingot 1 is rotated horizontally, the much more uniform structure is obtd.